VARIATIONS OF WAVE-ENERGY LEVELS AND COASTAL SEDIMENTATION, EASTERN NICARAGUA

Proceedings of the International Conference on Coastal Engineering

E.H. Roberts¹  E.H. Owens¹ 

[1] Coastal Studies Institute, Louisiana State University

关键词: wave energy;    energy level;    sedimentation;    Nicaragua;   

DOI  :  10.9753/icce.v16.%p

学科分类：建筑学

来源: Coastal Engineering Research Council

【 摘 要 】

High rates of weathering, abundant rainfall, and high discharge rates combine to supply large volumes of sediment to the coastal zone of eastern Nicaragua. This terrigenous sediment is confined to a narrow section of the inner shelf (<30 km wide) due to the circulation pattern within a coastal boundary layer. Sediment transport within the inner shelf and shore zone is to the south. This simple transport pattern is considerably modified by variations in wave-energy levels that are a function of shelf width, bottom friction, and wave sheltering. In northern sections, the shelf is up to 200 km wide but narrows to less than 20 km in the south. A direct result is that wave-energy levels at the shoreline are of the order of three times greater in the south. In the north the Rio Coco delta is propagating seaward in a fluvially dominated environment, whereas the Rio San Juan delta in the south has a wave-dominated morphology characterized by deflected distributaries. Other major accumulation features have developed where wave-shadowing is produced by offshore reefs and cays. Alongshore a spatial variation was recorded, with straight beaches and simple linear bars in the north that change to rhythmic beach topography and crescentic nearshore bars as wave-energy levels increase toward the south.

【 授权许可】

Unknown